Resin composition, resin molded product and method for producing resin molded product

Abstract

To provide a resin composition that can be suitably used to produce a resin molded product comprising AlN whiskers and having superior thermal conductivity, to provide a resin molded product comprising AlN whiskers and having superior thermal conductivity, and to provide a method for producing a resin molded product comprising AlN whiskers and having superior thermal conductivity.SOLUTION: A resin molded product according to the present invention comprises at least: an AlN whisker comprising a fibrous AlN single crystal and an oxygen-containing layer covering the surface of the AlN single crystal, with an aspect ratio of 5.0 or more and 50000 or less; and a resin material, wherein the content of the AlN whisker is 3.0 mass% or more and 65.0 mass% or less.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a resin composition, a resin molded article, and a method for producing a resin molded article. [Background technology]

[0002] As electronic devices become smaller and more powerful, the importance of thermal management in these devices is increasing. Due to concerns about the deterioration of the performance of electronic devices, it is necessary to dissipate heat to the outside of the electronic device as much as possible. In this regard, there is a demand for improving the thermal conductivity of resin parts used inside electronic devices.

[0003] Adding insulating fillers such as spherical ceramics is known as a method for improving the thermal conductivity of resin parts. In order to improve the thermal conductivity, it is important to increase the contact efficiency between the fillers to form a network (heat dissipation path). When spherical fillers are used, from the viewpoint of network formation, the spherical fillers are generally filled (added) into the resin material at a content of 70% by mass to 90% by mass. However, a high filling amount (content) of the filler causes problems such as an increase in the mass of the resin material (resin part) and a decrease in processability. In addition, the filling amount of the filler into the resin material is practically limited.

[0004] In view of this background, some of the inventors of the present application have conducted research and development of fibrous AlN whiskers that combine high thermal conductivity and high insulating properties (Patent Documents 1 and 2).

[0005] However, it remains unclear how much of the AlN whiskers disclosed in Patent Documents 1 and 2 should be filled into a resin material from the standpoints of thermal conductivity, processability, and other factors with a view to commercial use, and in what form the AlN whiskers should be added to the resin material. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2014-73951 A [Patent Document 2] JP 2018-154534 A Summary of the Invention [Problem to be solved by the invention]

[0007] The object of the present invention is to provide a resin composition that contains AlN whiskers and can be suitably used for producing a resin molded article having excellent thermal conductivity, to provide a resin molded article having AlN whiskers and excellent thermal conductivity, and to provide a method for producing a resin molded article having AlN whiskers and excellent thermal conductivity. [Means for solving the problem]

[0008] Such an object can be achieved by the present invention described below in (1) to (16). (1) A resin composition used for producing a resin molded product made of a material containing a resin material, A fiber-shaped AlN single crystal body, and an AlN whisker having an oxygen-containing layer covering the surface of the AlN single crystal body and an aspect ratio of 5.0 to 50,000; The resin material; At least A resin composition having an AlN whisker content of 3.0% by mass or more and 65.0% by mass or less.

[0009] (2) The resin composition according to (1) above, wherein the AlN whiskers have an average length in the minor axis direction of 0.1 μm or more and 50.0 μm or less.

[0010] (3) The resin composition according to (1) or (2) above, wherein the AlN whiskers have an average length in the major axis direction of 1.0 μm or more and 300 μm or less.

[0011] (4) The resin material is spherical, The resin composition according to any one of (1) to (3) above, which comprises a coating product formed by coating the surfaces of a plurality of the resin materials with a plurality of the AlN whiskers.

[0012] (5) The resin composition according to any one of (1) to (4) above, wherein the content of the AlN whiskers is 3.0% by mass or more and 20.0% by mass or less.

[0013] (6) The resin composition according to any one of (1) to (4) above, wherein the content of the AlN whiskers is 50.0% by mass or more and 65.0% by mass or less.

[0014] (7) A fiber-shaped AlN single crystal body, and an AlN whisker having an oxygen-containing layer covering the surface of the AlN single crystal body and an aspect ratio of 5.0 to 50,000; A resin material; At least The resin molded article has an AlN whisker content of 3.0% by mass or more and 65.0% by mass or less.

[0015] (8) The resin molded article according to (7) above, wherein the AlN whiskers have an average length in the minor axis direction of 0.1 μm or more and 50.0 μm or less.

[0016] (9) The resin molded article according to (7) or (8) above, wherein the AlN whiskers have an average length in the major axis direction of 1.0 μm or more and 300 μm or less.

[0017] (10) The resin material is spherical, The resin molded article according to any one of (7) to (9) above, which is made of a coated product formed by coating the surfaces of a plurality of the resin materials with a plurality of the AlN whiskers.

[0018] (11) The resin molded article according to any one of (7) to (10) above, which is formed by impregnating a sheet-like formation in which a plurality of the AlN whiskers are in contact with one another to form a network, with the resin material.

[0019] (12) The number of contact points, which is the total number of contact points between the AlN whiskers per unit volume, is 0.015 / μm 3 More than 1.0 / μm 3 The resin molded article according to any one of the above (7) to (11), which is:

[0020] (13) The resin molded article according to any one of (7) to (12) above, wherein the content of the AlN whiskers is 3.0% by mass or more and 20.0% by mass or less.

[0021] (14) The resin molded article according to any one of (7) to (12) above, wherein the content of the AlN whiskers is 50.0% by mass or more and 65.0% by mass or less.

[0022] (15) A fiber-shaped AlN single crystal body, and an AlN whisker having an oxygen-containing layer covering the surface of the AlN single crystal body and an aspect ratio of 5.0 to 50,000; A resin material; A method for producing a resin molded product comprising at least forming a sheet-like structure in which a plurality of the AlN whiskers are in contact with each other to form a network; impregnating the sheet-like product with the resin material; A method for producing a resin molded product comprising the steps of:

[0023] (16) A fiber-shaped AlN single crystal body, and an AlN whisker having an oxygen-containing layer covering the surface of the AlN single crystal body and an aspect ratio of 5.0 to 50,000; A spherical resin material; A method for producing a resin molded product comprising at least forming a coated structure in which the surfaces of a plurality of the resin materials are each coated with a plurality of the AlN whiskers; pressing the formed coating formation; A method for producing a resin molded product comprising the steps of: Effect of the Invention

[0024] According to the present invention, it is possible to provide a resin composition that can be suitably used for producing a resin molded article containing AlN whiskers and having excellent thermal conductivity, to provide a resin molded article containing AlN whiskers and having excellent thermal conductivity, and to provide a method for producing a resin molded article containing AlN whiskers and having excellent thermal conductivity. [Brief description of the drawings]

[0025] [Figure 1] FIG. 1 is a schematic diagram showing the configuration of the resin molded body according to the first embodiment. [Diagram 2] FIG. 2 is a schematic diagram showing the configuration of a resin molded body according to the second embodiment. [Diagram 3] FIG. 3 is a schematic diagram showing the configuration of a resin molded body according to a third embodiment. [Figure 4] FIG. 4 is a schematic diagram showing the configuration of a resin molded body according to the fourth embodiment. [Diagram 5] FIG. 5 is a graph showing the relationship between the mass ratio of AlN whiskers to the resin molded body and the thermal conductivity for Examples 1 to 3, 7 to 14 and Comparative Examples 1 and 2. [Figure 6] FIG. 6 is a graph showing the relationship between the number of contact points and thermal conductivity for the resin molded bodies of Examples 1 to 6 (each of the resin molded bodies relating to the first embodiment) and the resin molded bodies of Examples 11 to 17 (each of the resin molded bodies relating to the fourth embodiment) based on the measurement results shown in Table 9. [Figure 7] FIG. 7 is a graph showing the relationship between the number of contact points and thermal conductivity for each of four types of average diameter (average length in the minor axis direction) based on the measurement results shown in Table 9. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] Various embodiments of the present invention will now be described with reference to the accompanying drawings, in which like reference numerals refer to like elements throughout the drawings, and it should be noted that the drawings are not necessarily drawn to scale.

[0027] [1] Resin composition First, the resin composition of the present invention will be described.

[0028] The resin composition of the present invention is a resin composition used for producing a resin molded product composed of a material containing a resin material, and comprises at least a fibrous AlN single crystal, AlN whiskers having an oxygen-containing layer covering the surface of the AlN single crystal and an aspect ratio of 5.0 to 50,000, and a resin material. The content of the AlN whiskers is 3.0% by mass to 65.0% by mass.

[0029] This makes it possible to provide a resin composition that is suitable for use in producing a resin molded article having AlN whiskers and excellent thermal conductivity, and also makes it possible to provide a resin molded article produced using the resin composition with excellent processability.

[0030] However, if the above conditions are not met, satisfactory results will not be obtained. For example, if the aspect ratio of the AlN whiskers is less than the lower limit, it becomes difficult to sufficiently increase the contact efficiency between the AlN whiskers in the resin molded body produced using the resin composition, and the thermal conductivity of the resin molded body cannot be made sufficiently excellent.

[0031] In addition, when the aspect ratio of the AlN whiskers exceeds the upper limit, the moldability when a resin molded body is manufactured using the resin composition is significantly reduced. In addition, air is easily entrained during the manufacture of the resin molded body, particularly during kneading, and the thermal conductivity of the manufactured resin molded body is easily reduced. In addition, the processability when processing the manufactured resin molded body is significantly reduced.

[0032] Furthermore, if the content of AlN whiskers in the resin composition is less than the lower limit, the thermal conductivity of a resin molded article produced using the resin composition cannot be made sufficiently excellent.

[0033] In addition, if the content of AlN whiskers in the resin composition exceeds the upper limit, the moldability when a resin molded product is manufactured using the resin composition is significantly reduced. In addition, air is easily entrained during the manufacture of the resin molded product, particularly during kneading, and the thermal conductivity of the manufactured resin molded product is easily reduced. In addition, the processability when processing the manufactured resin molded product is significantly reduced.

[0034] [1-1]AlN whiskers The resin composition of the present invention contains a fibrous AlN single crystal, and AlN whiskers having an aspect ratio of 5.0 or more and 50,000 or less and having an oxygen-containing layer covering the surface of the AlN single crystal.

[0035] The aspect ratio of the AlN whiskers, that is, the ratio of the length of the AlN whiskers in the major axis direction to the length of the AlN whiskers in the minor axis direction, may be 5.0 or more and 50,000 or less.

[0036] The AlN whiskers mainly include a fibrous AlN single crystal and an oxygen-containing layer that covers the surface of the AlN single crystal in a cylindrical shape. The AlN whiskers may also include, for example, a hydrophobic layer that covers the oxygen-containing layer in a cylindrical shape on the outer side of the oxygen-containing layer.

[0037] The average length in the minor axis direction of the AlN whiskers is preferably 0.1 μm or more and 50.0 μm or less, more preferably 0.5 μm or more and 15.0 μm or less, and even more preferably 1.0 μm or more and 10.0 μm or less.

[0038] This makes it possible to further increase the contact efficiency between AlN whiskers, thereby improving the thermal conductivity of the resin molded article produced using the resin composition of the present invention, as well as improving the moldability of the resin composition of the present invention and the processability of the resin molded article produced using the resin composition of the present invention.

[0039] In this specification, the average length in the short axis direction of AlN whiskers refers to the sum of the average lengths in the short axis direction of all AlN whiskers contained within a specified range (e.g., a cube of 500 μm × 500 μm × 500 μm) divided by the number of AlN whiskers contained within the specified range.

[0040] It is also preferable that the minimum and maximum average lengths in the minor axis direction of the plurality of AlN whiskers contained in the resin composition of the present invention are within the above ranges. This makes the above-mentioned effects more pronounced.

[0041] The average length in the major axis direction of the AlN whiskers can be, for example, from 1.0 μm to 5.0 cm, and is preferably from 1.0 μm to 300 μm.

[0042] This makes it possible to further increase the contact efficiency between AlN whiskers, thereby improving the thermal conductivity of the resin molded article produced using the resin composition of the present invention, as well as improving the moldability of the resin composition of the present invention and the processability of the resin molded article produced using the resin composition of the present invention.

[0043] In this specification, the average length in the long axis direction of AlN whiskers refers to the sum of the average lengths in the long axis direction of all AlN whiskers contained within a specified range (e.g., a cube of 500 μm × 500 μm × 500 μm) divided by the number of AlN whiskers contained within the specified range.

[0044] It is also preferable that the minimum and maximum average lengths in the major axis direction of the plurality of AlN whiskers contained in the resin composition of the present invention are within the above ranges. This makes the above-mentioned effects more pronounced.

[0045] As described above, the content of the AlN whiskers in the resin composition of the present invention may be from 3.0% by mass to 65.0% by mass.

[0046] For example, when particular importance is placed on the moldability when producing a resin formed body using the resin composition of the present invention, or the processability of a resin formed body produced using the resin composition of the present invention, the content of the AlN whiskers in the resin composition of the present invention is preferably 3.0 mass% or more and 20.0 mass% or less, and more preferably 5.0 mass% or more and 20.0 mass% or less.

[0047] Furthermore, for example, when the thermal conductivity of the resin formed body using the resin composition of the present invention is particularly important, the content of the AlN whiskers in the resin composition of the present invention is preferably 50.0 mass % or more and 65.0 mass % or less.

[0048] [1-2] Resin materials The resin composition of the present invention contains a resin material in addition to the above-mentioned AlN whiskers. This makes it possible to ensure, for example, moldability and processability.

[0049] The resin material may be contained in the resin composition of the present invention in any form, but it is preferably spherical, and the surface of each of the plurality of resin materials is coated with a plurality of AlN whiskers. In other words, the resin composition of the present invention preferably contains a plurality of coated formations in which a plurality of AlN whiskers are attached to the surface of a spherical resin material.

[0050] Furthermore, when the resin material is spherical, the average particle size of the resin material is preferably 1.0 μm or more and 200.0 μm or less, more preferably 5.0 μm or more and 100.0 μm or less, and even more preferably 10.0 μm or more and 50.0 μm or less.

[0051] As the resin material, for example, a thermosetting resin such as a silicone resin, an epoxy resin, a phenol resin, a melamine resin, a urea resin, a thermosetting polyimide, an unsaturated polyester resin, or a polyurethane can be used.

[0052] As the resin material, for example, thermoplastic resins such as polyethylene, polypropylene, polystyrene, polyvinyl chloride, polyvinylidene chloride, polyvinyl acetate, acrylonitrile-styrene copolymer, acrylonitrile-butadiene-styrene copolymer, acrylonitrile-ethylene-propylene-diene-styrene copolymer, and methacrylic resin can be used.

[0053] As the resin material, for example, a fluororesin such as polytetrafluoroethylene, polychlorotrifluoroethylene, polyvinylidene fluoride, or polyvinyl fluoride can be used.

[0054] Examples of the resin material that can be used include polycarbonate, polyamide resin, polyacetal, polyethylene terephthalate, polybutylene terephthalate, polyether ether ketone, polyphenyl sulfide, polysulfone, polyetherimide, polyamideimide, thermoplastic polyimide, and liquid crystal polymer.

[0055] Furthermore, examples of resin materials that can be used include acrylonitrile styrene acrylate, atactic polypropylene, cellulose acetate, cellulose acetate butyrate, chlorinated vinyl chloride, chloroprene rubber, diallyl phthalate, ethylene ethyl acrylate, ethylene propylene diene terpolymer, ethylene tetrafluoroethylene copolymer, ethylene vinyl acetate copolymer, ethyl vinyl ether, ethylene vinyl alcohol copolymer, perfluoro rubber, tetrafluoroethylene-hexafluoropropylene copolymer, and soft urethane foam.

[0056] Furthermore, examples of resin materials that can be used include glass fiber reinforced plastics, glass fiber reinforced thermoplastics, butyl rubber, ionomers, isoprene rubber, melamine formaldehyde, methyl methacrylate, nitrile rubber, natural rubber, polyacrylic acid, polyaryl ether ketone, polyester alkyd resins, polyacrylonitrile, and polyarylate.

[0057] Furthermore, examples of resin materials that can be used include polyparaphenylene benzobisoxazole, polybutadiene styrene, diallyl terephthalate, polydicyclopentadiene, polyethylene naphthalate, polyethylene oxide, polyethersulfone, phenol formaldehyde, tetrafluoroethylene perfluoroalkyl vinyl ether copolymer, polyisobutylene, and polymethylpentene.

[0058] Furthermore, examples of resin materials that can be used include polyphthalamide, polyphenylene ether, polyphenylene oxide, polytrimethylene terephthalate, reactive polyurethane, polyvinyl alcohol, polyvinyl butyral, acrylic modified polyvinyl chloride, polyvinyl dichloride, and vinyl chloride vinyl acetate copolymers.

[0059] Furthermore, examples of resin materials that can be used include polyvinyl formal, polyvinylpyrrolidone, styrene butadiene, styrene butadiene rubber, styrene block copolymers, styrene butadiene styrene block copolymers, styrene ethylene butylene styrene block copolymers, styrene ethylene propylene styrene block copolymers, styrene isoprene styrene block copolymers, sheet molding compounds, syndiotactic polystyrene, thermoplastic elastomers, thermoplastic polyurethanes, urea formaldehyde resins, ultra-high molecular weight polyethylene, vinyl chloride ethylene, vinyl chloride octyl acrylate, and cross-linked polyethylene.

[0060] The content of the resin material in the resin composition of the present invention is preferably 35.0% by mass or more and 97.0% by mass or less.

[0061] [1-3] Spherical AlN filler The resin composition of the present invention may further contain spherical AlN filler.

[0062] This can further increase the overall thermal conductivity of a resin molded product produced using the resin composition of the present invention. More specifically, for example, in a sheet-shaped resin molded product, a heat transfer path can be suitably formed not only in the in-plane direction of the resin molded product but also in the thickness direction, and the balance of the thermal conductivity in the in-plane direction and the thickness direction can be made more suitable.

[0063] The average particle size of the spherical AlN filler is not particularly limited, but is preferably 0.1 μm or more and 150 μm or less.

[0064] In this specification, unless otherwise specified, the average particle size means the particle size at which the frequency becomes 50% when the particle amount is cumulatively calculated from the small particle size side in the particle distribution measured by image analysis, and can be determined, for example, by measurement using a particle shape image analyzer "PITA-04" (manufactured by Seishin Enterprise Co., Ltd.).

[0065] When the resin composition of the present invention contains spherical AlN filler, the content of the spherical AlN filler in the resin composition of the present invention is preferably 60.0 mass % or more and 70.0 mass % or less.

[0066] [1-4] Other ingredients The resin composition of the present invention may contain components other than those described above. Hereinafter, in this section, such components will be referred to as "other components".

[0067] Examples of other components include plasticizers, dispersants, colorants, antioxidants, UV absorbers, light stabilizers, softeners, modifiers, rust inhibitors, fillers other than those mentioned above (for example, AlN whiskers having an aspect ratio outside the range of 5.0 to 50,000, whiskers made of materials other than AlN, spherical fillers made of materials other than AlN, etc.), bulking agents, electromagnetic wave absorbing materials, surface lubricants, corrosion inhibitors, heat stabilizers, lubricants, primers, antistatic agents, polymerization inhibitors, crosslinking agents, catalysts, leveling agents, thickeners, dispersants, antioxidants, flame retardants, hydrolysis inhibitors, and corrosion inhibitors.

[0068] However, the content of other components in the resin composition of the present invention is preferably 10% by mass or less, more preferably 7% by mass or less, and even more preferably 5% by mass or less.

[0069] In particular, when "fillers other than those mentioned above" are included, the ratio of the content of "fillers other than those mentioned above" to the content of the AlN whiskers mentioned above is preferably 15 mass% or less, more preferably 10 mass% or less, and even more preferably 5 mass% or less.

[0070] [2] Resin molded body Next, the resin molded article of the present invention will be described.

[0071] The resin molded body of the present invention comprises at least a fiber-shaped AlN single crystal, AlN whiskers having an oxygen-containing layer covering the surface of the AlN single crystal and an aspect ratio of 5.0 to 50,000, and a resin material. The content of the AlN whiskers is 3.0% by mass to 65.0% by mass.

[0072] This makes it possible to provide a resin molded article having AlN whiskers and excellent thermal conductivity, and also makes it possible to improve the processability of the resin molded article.

[0073] The resin molded article of the present invention may be produced using any material, but can be suitably produced by using the above-mentioned resin composition of the present invention.

[0074] When the above-described resin composition of the present invention is used to produce the resin molded article of the present invention, other components and other compositions may be used in combination with the resin composition.

[0075] The components contained in the resin molded product of the present invention can be, for example, those that satisfy the condition described in [1] above.

[0076] This provides the same effect as described above. More specifically, it is preferable to satisfy the following conditions, for example:

[0077] For example, the average length in the minor axis direction of the AlN whiskers contained in the resin molded product of the present invention is preferably 0.1 μm or more and 50.0 μm or less, more preferably 0.5 μm or more and 15.0 μm or less, and even more preferably 1.0 μm or more and 10.0 μm or less.

[0078] This can further increase the contact efficiency between AlN whiskers, thereby improving the thermal conductivity of the resin molded article of the present invention and also improving the processability of the resin molded article of the present invention.

[0079] Furthermore, it is preferable that the minimum and maximum average lengths in the minor axis direction of the plurality of AlN whiskers contained in the resin molded article of the present invention are within the above ranges. This makes the above-mentioned effects more pronounced.

[0080] The average length in the major axis direction of the AlN whiskers contained in the resin molded article of the present invention can be, for example, from 1.0 μm to 5.0 cm, and is preferably from 1.0 μm to 300 μm.

[0081] This can further increase the contact efficiency between AlN whiskers, thereby improving the thermal conductivity of the resin molded article of the present invention and also improving the processability of the resin molded article of the present invention.

[0082] It is also preferable that the minimum and maximum average lengths in the major axis direction of the plurality of AlN whiskers contained in the resin molded article of the present invention are within the above ranges. This makes the above-mentioned effects more pronounced.

[0083] The resin material may be contained in the resin molded product of the present invention in any form, but it is preferably spherical, and the surface of each of the plurality of resin materials is coated with a plurality of AlN whiskers. In other words, the resin molded product of the present invention preferably contains a plurality of coated formations in which a plurality of AlN whiskers are attached to the surface of a spherical resin material.

[0084] This makes it possible to form an efficient heat dissipation path even with the addition of a small amount of AlN whiskers.

[0085] As described above, the content of the AlN whiskers in the resin molded article of the present invention may be from 3.0% by mass to 65.0% by mass.

[0086] For example, when the processability of the resin molded body of the present invention is particularly important, the content of the AlN whiskers in the resin molded body of the present invention is preferably 3.0 mass% or more and 20.0 mass% or less, and more preferably 5.0 mass% or more and 20.0 mass% or less.

[0087] Furthermore, for example, when particular importance is attached to the thermal conductivity of the resin formed body of the present invention, the content of the AlN whiskers in the resin formed body of the present invention is preferably 50.0 mass % or more and 65.0 mass % or less.

[0088] In the case of producing the resin molded product of the present invention using the resin composition of the present invention, the conditions of any component contained in the resin molded product may be different from the conditions of the component contained in the resin composition. For example, the length of the AlN whiskers in the resin molded product in the long axis direction may be shorter than the length of the AlN whiskers in the resin composition.

[0089] The number of contact points, which is the total number of contact points between the AlN whiskers per unit volume in the resin molded body, is 0.015 / μm 3 More than 1.0 / μm 3 Preferably, it is 0.016 / μm or less. 3 More than 1.0 / μm 3 More preferably, it is 0.020 / μm or less. 3 More than 0.046 / μm 3 More preferably, it is 0.023 / μm or less. 3 More than 0.029 / μm 3 Most preferably, it is:

[0090] This makes it possible to provide the resin molded body with sufficiently excellent processability and also with better thermal conductivity.

[0091] In this specification, the "number of contact points" refers to the number of contact points between the multiple AlN whiskers filled in the resin molded body per unit volume (μm 3The "number of contact points" refers to the total number of contact points per 500 μm × 500 μm × 500 μm cube. For example, the number of contact points of AlN whiskers in a cube of 500 μm × 500 μm × 500 μm is measured, and the number of contact points thus measured is multiplied by 125,000,000 (= 500 3 )μm 3 By dividing by this, the calculated value can be adopted.

[0092] In the present invention, the resin molded body preferably has a low porosity. This can provide the resin molded body with better thermal conductivity.

[0093] A resin molded article having a sufficiently low porosity can be suitably produced by including AlN whiskers that satisfy the above-mentioned conditions.

[0094] Hereinafter, preferred embodiments of the resin molded article and the method for producing the resin molded article of the present invention will be described more specifically.

[0095] [2-1] First embodiment An overview of the resin molded body according to the first embodiment will be described with reference to Fig. 1. Fig. 1 is a schematic diagram showing a configuration of the resin molded body 1 according to the first embodiment.

[0096] The resin molded body 1 according to the first embodiment mainly includes a sheet-like formation 10 in which a plurality of AlN whiskers 11 come into contact with one another to form a network, and a resin material 20. The network-formed sheet-like formation 10 refers to a thin sheet in which a number of AlN whiskers 11 are entangled and come into contact with one another to form a large number of heat dissipation paths by the plurality of AlN whiskers 11. The resin molded body 1 according to the first embodiment is formed by impregnating the sheet-like formation 10 with the resin material 20.

[0097] With this configuration, the AlN whiskers can form a heat dissipation path more efficiently.

[0098] The resin molded body 1 can be produced, for example, as follows. First, AlN whiskers 11 manufactured by a known method are prepared, and then a plurality of AlN whiskers 11 are dispersed in a predetermined solvent, followed by a paper-making process to produce a paper-like intermediate product in which the plurality of AlN whiskers 11 are dispersed uniformly to a certain degree. This intermediate product is then pressed in a press at a predetermined pressure for a predetermined time to form a sheet-like product 10. As the predetermined solvent, water or various organic solvents can be used. When an organic solvent is used as the predetermined solvent, for example, a polar solvent such as ethanol or propanol can be suitably used. The predetermined pressure is, for example, 10 kg / cm. 2 More than 100kg / cm 2 The pressure can be set to the following range. The above-mentioned predetermined time can be, for example, 5 minutes or more and 60 minutes or less. The pressing of the intermediate product using a press is usually intended to remove a predetermined solvent contained in the intermediate product. Therefore, when the content of the predetermined solvent contained in the intermediate product is small, the step of pressing the intermediate product with a press may be omitted, and the intermediate product produced as described above may be used as it is as the sheet-like product 10.

[0099] The formed sheet-like formation 10 is then placed on a predetermined mold, and the mold is impregnated with liquid resin material 20, after which the resin material 20 is solidified to form the resin molded body 1.

[0100] [2-2] Second embodiment Next, a second embodiment will be described with reference to FIG. 2. However, the description of the same points as in the previous embodiment will be omitted and the description will focus on the differences. FIG. 2 is a schematic diagram showing the configuration of a resin molded body 2 according to the second embodiment.

[0101] The resin molded body 2 according to the second embodiment mainly includes a plurality of AlN whiskers 11, the resin material 20 explained above, and spherical AlN fillers 30.

[0102] The resin molded body 2 according to the second embodiment can be formed, for example, by preparing in advance a plurality of AlN whiskers 11 manufactured by a known method and a plurality of spherical AlN fillers 30 manufactured by a known method, placing them in a predetermined mold so as to be uniformly dispersed, impregnating the mold with a liquid resin material 20, and then solidifying the resin material 20. The resin molded body 2 thus formed does not have the sheet-like object 10 included in the resin molded body 1 according to the first embodiment described above.

[0103] When the content of the spherical AlN fillers 30 in the resin molding 2 is, for example, 60.0 mass% or more and 70.0 mass% or less, the content of the AlN whiskers 11 in the resin molding 2 is preferably 3.0 mass% or more and 20.0 mass% or less, more preferably 5.0 mass% or more and 20.0 mass% or less, and even more preferably 5.0 mass% or more and 10.0 mass% or less.

[0104] This makes it possible to improve the thermal conductivity of the resin molded body 2 and also improve the processability of the resin molded body.

[0105] [2-3] Third embodiment Next, a third embodiment will be described with reference to FIG. 3. However, the description of the same points as in the above-described embodiment will be omitted and the description will focus on the points of difference. FIG. 3 is a schematic diagram showing the configuration of a resin molded body 3 according to the third embodiment.

[0106] The resin molded body 3 according to the third embodiment mainly includes a plurality of AlN whiskers 11 and a spherical resin material 50. In the resin molded body 3 according to the third embodiment, a coating formation 40 is formed in which the surface of each of the plurality of resin materials 50 is coated with a plurality of AlN whiskers 11, as shown in Fig. 3. In other words, the resin molded body 3 according to the third embodiment includes the coating formation 40 as a substitute for the sheet-like formation 10 in the resin molded body 1 according to the first embodiment.

[0107] The resin molded body 3 can be produced, for example, as follows. That is, the resin molding 3 can be formed, for example, by preparing in advance a plurality of AlN whiskers 11 manufactured by a known method and a plurality of spherical resin materials 50, forming a coated formation 40 in which the surfaces of each of the plurality of resin materials 50 are coated with a plurality of AlN whiskers 11, placing this coated formation 40 on a predetermined mold, pressing the coated formation 40 with a predetermined pressure, and performing a heat treatment at a predetermined temperature. This allows the AlN whiskers to form a more efficient heat dissipation path.

[0108] [2-4] Fourth embodiment Next, a fourth embodiment will be described with reference to FIG. 4. However, the description of the same points as in the above-described embodiment will be omitted, and the description will focus on the points of difference. FIG. 4 is a schematic diagram showing the configuration of a resin molded body 4 according to the fourth embodiment.

[0109] The resin molded body 4 according to the fourth embodiment mainly includes a plurality of AlN whiskers 11 and a resin material 20. The resin molded body 4 according to the fourth embodiment is similar to the resin molded body 1 according to the first embodiment, but does not use the sheet-like formed material 10 of the resin molded body 1, and instead uses the plurality of AlN whiskers 11 each crushed to shorten their length in the long axis direction. The length in the long axis direction of the plurality of AlN whiskers 11 in the resin molded body 4 according to the fourth embodiment is generally 1.0 μm or more and 300.0 μm or less, but is not limited thereto, and may be any length shorter than the length in the long axis direction of the AlN whiskers used in the resin molded body 1 according to the first embodiment.

[0110] The resin molding 4 of the fourth embodiment can be formed, for example, by preparing a plurality of AlN whiskers 11 manufactured by a known method in advance, crushing the AlN whiskers 11 so that their length in the long axis direction falls within a predetermined range, dispersing the crushed AlN whiskers 11 in liquid resin material 20, placing the liquid resin material 20 in which the plurality of AlN whiskers 11 are dispersed in a predetermined mold, and then solidifying the resin material 20.

[0111] The content of the AlN whiskers 11 in the resin molded body 4 according to the fourth embodiment may be from 3.0 mass % to 65.0 mass % as described above, but is preferably from 20.0 mass % to 40.0 mass %.

[0112] Although the preferred embodiments of the present invention have been described above, the present invention is not limited to the above.

[0113] For example, the above description has been given of the case where the resin composition of the present invention is used to produce the resin molded body of the present invention, but the resin molded body of the present invention is not limited to those produced by the above-mentioned method. EXAMPLES

[0114] Next, specific examples of the present invention will be described. [3] Preparation of resin composition and production of resin molded product (Examples 1 to 6) A large number of AlN whiskers produced by a known method were dispersed in water, and then the mixture was filtered for 10 minutes to obtain a paper-like intermediate product in which the AlN whiskers were uniformly dispersed to a certain degree. The intermediate product was then subjected to a pressure of 40 kg / cm 2 The mixture was pressed in a press at a pressure of 1000 for 30 minutes to form a sheet-like product.

[0115] Next, the formed sheet-like product was placed in a predetermined mold, liquid epoxy resin was added to the mold, and the mold was heated at 80° C. for 3 hours and then at 150° C. for 1 hour in a curing step to cure the epoxy resin, thereby obtaining a resin molded product. In each of Examples 1 to 6, AlN whiskers were contained according to the conditions shown in Table 1, and liquid epoxy resin was added so that the content of AlN whiskers in the resin molded product was as shown in Table 1.

[0116] The resin molded bodies according to Examples 1 to 6 correspond to the resin molded body 1 according to the above-described first embodiment.

[0117] [Table 1]

[0118] (Examples 7 and 8) A plurality of spherical AlN fillers manufactured by a known method were added and dispersed in a liquid epoxy resin, and then a number of AlN whiskers manufactured by a known method were added and dispersed in the epoxy resin to prepare a slurry as a resin composition. The slurry was uniformly placed in a predetermined mold, and the mold was heated at 80°C for 3 hours, and then further heated at 150°C for 1 hour in a curing process to cure the epoxy resin and obtain a resin molded body. In Examples 4 and 5, AlN whiskers were contained under the conditions shown in Table 2, and liquid epoxy resin was added so that the content of AlN whiskers in the resin molded body was as shown in Table 2. The value in parentheses in Table 2 indicates the sum of the content of AlN whiskers and the content of spherical AlN fillers in the resin molded body.

[0119] The resin molded bodies according to Examples 7 and 8 correspond to the resin molded body 2 according to the second embodiment described above.

[0120] [Table 2]

[0121] (Examples 9 and 10) A large number of AlN whiskers manufactured by a known method and a large number of spherical phenolic resins were prepared. Then, a coating product was formed as a resin composition such that the surface of each of the plurality of phenolic resins was coated with the plurality of AlN whiskers.

[0122] Next, the coated product thus formed was placed in a predetermined mold, and the coated product was heated at 180°C for 5 minutes while being pressurized to cure the phenolic resin, thereby obtaining a resin molded product. In Examples 9 and 10, the AlN whiskers were contained as shown in Table 3, and the coated product was formed so that the content of AlN whiskers in the resin molded product was as shown in Table 3.

[0123] The resin molded bodies according to Examples 9 and 10 correspond to the resin molded body 3 according to the above-described third embodiment.

[0124] [Table 3]

[0125] (Examples 11 to 20) A large number of AlN whiskers manufactured by a known method were crushed until the length in the long axis direction reached a predetermined value. Next, a large number of the crushed AlN whiskers were dispersed in a liquid epoxy resin to obtain a resin composition. This resin composition was placed in a predetermined mold, and the mold was heated at 80°C for 3 hours, and then further heated at 150°C for 1 hour in a curing process to cure the epoxy resin and obtain a resin molded body. In each of Examples 11 to 20, AlN whiskers were contained under the conditions shown in Table 4, and the AlN whiskers were dispersed in the liquid epoxy resin so that the content of AlN whiskers in the resin molded body was as shown in Table 4.

[0126] The resin molded bodies according to Examples 11 to 20 correspond to the resin molded body 4 according to the above-mentioned fourth embodiment.

[0127] [Table 4]

[0128] (Comparative Examples 1 and 2) As Comparative Examples 1 and 2, a commercially available resin molded product to which only spherical AlN fillers were added was used. The resin material used in this commercially available product was silicone resin. The content of the AlN filler in the resin molded products according to Comparative Examples 1 and 2 is as shown in Table 5.

[0129] [Table 5]

[0130] (Comparative Examples 3 to 5) A resin molding was produced in the same manner as in Example 1, except that the AlN whiskers were contained according to the conditions shown in Table 6, and a liquid epoxy resin was added so that the content of AlN whiskers in the resin molding was as shown in Table 6.

[0131] [Table 6]

[0132] Comparative Example 6 A resin molding was produced in the same manner as in Example 11, except that the AlN whiskers were dispersed in the liquid epoxy resin so that the AlN whisker content in the resin molding was as shown in Table 7 and contained as shown in Table 7.

[0133] [Table 7]

[0134] [4] Evaluation The thermal conductivity of the resin molded body according to each of the examples and each of the comparative examples was measured. The thermal conductivity of these was calculated from the product of the thermal diffusivity, the specific heat, and the density. The thermal diffusivity was measured using a LaserPIT device manufactured by Advance Riko Co., Ltd., the specific heat was measured using a DSC-60A manufactured by Shimadzu Corporation, and the density was measured using an AD-1653 manufactured by A&D Co., Ltd. Table 8 shows the results of the thermal conductivity of the resin molded body according to each of the examples and each of the comparative examples. FIG. 5 is a diagram showing the relationship between the mass ratio of AlN whiskers to the resin molded body and the thermal conductivity for Examples 1 to 3, 7 to 14, and Comparative Examples 1 and 2.

[0135] [Table 8]

[0136] 5, the resin molded bodies according to each Example had excellent thermal conductivity while containing a small amount of AlN whiskers. In addition, when Example 8 is compared with Comparative Example 1 (Example 8 can be understood as Comparative Example 1 to which 5.0 mass % of AlN whiskers has been additionally added), the thermal conductivity of Example 8 was higher than that of Comparative Example 1.

[0137] From the above results, it is understood that a network (heat dissipation path) caused by AlN whiskers is efficiently formed in the resin molded body according to each of the above examples. In particular, it is considered that such a network is more efficiently formed in the resin molded body including the sheet-shaped product.

[0138] [5] Experimental data Table 9 shows the results of measurements performed for Examples 1 to 6, 11 to 20 and Comparative Examples 3 to 6. In Table 9, "filling amount [wt%]" indicates the filling amount (unit: mass%) of AlN whiskers 11 filled in the resin molded body, "filling amount [vol%]" indicates the filling amount (unit: volume%) of AlN whiskers 11 filled in the resin molded body, and "thermal conductivity" indicates the thermal conductivity of the resin molded body. Also, in Table 9, "average diameter" indicates the average length of the AlN whiskers in the minor axis direction.

[0139] In Table 9, the "number of contact points per volume" is calculated by measuring the number of contact points of AlN whiskers in a cube of 500 μm × 500 μm × 500 μm, and dividing the number of contact points by 500 μm. 3 The number of contact points is calculated by dividing the measured value by the measured value. The number of contact points is measured by taking an X-ray CT image of each sample and performing image analysis processing using a computer on the taken X-ray CT image.

[0140] FIG. 6 shows the results of the measurements shown in Table 9 for the resin molded bodies of Examples 1 to 6 (resin molded bodies according to the first embodiment) and the resin molded bodies of Examples 11 to 17 (resin molded bodies according to the fourth embodiment). 1 is a graph showing the relationship between the number of contact points and thermal conductivity.

[0141] [Table 9]

[0142] As is clear from Table 9 and FIG. 6, in the resin molded body according to the fourth embodiment (the resin molded bodies of Examples 11 to 17), the number of contact points was 0.012 / μm 3 When the number of contacts is 0.015 / μm, the thermal conductivity is 1.5W / mk. 3 When θ is 0.05, the thermal conductivity increases to 2.0 W / mK, following a quadratic curve.

[0143] In addition, the number of contact points is 0.01 / μm 3 When the number of contacts is 0.016 / μm, the thermal conductivity is 2.0W / mk. 3 When θ is 0.05, the thermal conductivity increases to 3.0 W / mK, following a quadratic curve.

[0144] Focusing on the resin molded body according to the first embodiment (the resin molded bodies of Examples 1 to 6), the number of contact points is 0.014 / μm 3 When the number of contacts is 0.020 / μm, the thermal conductivity is 4.0W / mk. 3 When the temperature is 100°C, the thermal conductivity increases to 4.7 W / mK.

[0145] In addition, the number of contact points is 0.020 / μm 3 When the number of contacts is 0.023 / μm, the thermal conductivity is 4.7W / mk. 3 When θ is 0, the thermal conductivity increases to 5.3 W / mK, following a quadratic curve.

[0146] FIG. 7 is a graph showing the relationship between the number of contact points and thermal conductivity for each of four types of average diameters (average length in the minor axis direction) based on the measurement results shown in Table 9. Here, the four types of average diameters (average length in the minor axis direction) include the ranges of less than 1 μm, 1 μm or more and less than 5 μm, 5 μm or more and less than 10 μm, and 10 μm or more. Note that these four types of average diameters (average length in the minor axis direction) do not distinguish between the resin molded body according to the first embodiment (resin molded bodies of Examples 1 to 6) and the resin molded body according to the fourth embodiment (resin molded bodies of Examples 11 to 17). In addition, in the graph shown in FIG. 7, the horizontal axis is expressed in logarithmic notation.

[0147] As is clear from Table 9 and FIG. 7, when the number of contact points is the same or approximately the same, the thermal conductivity is significantly higher when the average diameter is 1 μm or more and 10 μm or less than the thermal conductivity when compared to when the average diameter is less than 1 μm. [Explanation of symbols]

[0148] 1 Resin molding 2. Resin molding 3. Resin molding 4. Resin molding 10 Sheet-like formation 11 AlN whiskers 20 Resin materials 30 Spherical AlN filler 40 Coating Formation 50 Resin materials

Claims

1. A resin composition used in the manufacture of a resin molded product made of a material containing a resin material, A fiber-shaped AlN single crystal body, and an AlN whisker having an oxygen-containing layer covering the surface of the AlN single crystal body and an aspect ratio of 5.0 to 50,000; The resin material; At least A resin composition having an AlN whisker content of 3.0 mass % or more and 65.0 mass % or less.

2. The resin composition according to claim 1 , wherein the AlN whiskers have an average length in the minor axis direction of 0.1 μm or more and 50.0 μm or less.

3. The resin composition according to claim 1 or 2, wherein the AlN whiskers have an average length in the major axis direction of 1.0 μm or more and 300 μm or less.

4. The resin material is spherical, 3. The resin composition according to claim 1, comprising a coating formed by coating a surface of each of a plurality of said resin materials with a plurality of said AlN whiskers.

5. The resin composition according to claim 1 or 2, wherein the content of the AlN whiskers is 3.0 mass % or more and 20.0 mass % or less.

6. The resin composition according to claim 1 or 2, wherein the content of the AlN whiskers is 50.0 mass % or more and 65.0 mass % or less.

7. A fiber-shaped AlN single crystal body, and an AlN whisker having an oxygen-containing layer covering the surface of the AlN single crystal body and an aspect ratio of 5.0 to 50,000; A resin material; At least The content of the AlN whiskers is 3.0% by mass or more and 65.0% by mass or less.

8. 8. The resin molded article according to claim 7, wherein the AlN whiskers have an average length in the minor axis direction of 0.1 μm or more and 50.0 μm or less.

9. 9. The resin molded article according to claim 7, wherein the AlN whiskers have an average length in the major axis direction of 1.0 μm or more and 300 μm or less.

10. The resin material is spherical, 9. The resin molded body according to claim 7, comprising a coated structure formed by coating a surface of each of a plurality of said resin materials with a plurality of said AlN whiskers.

11. 9. The resin molded article according to claim 7, which is formed by impregnating a sheet-like formation in which a plurality of the AlN whiskers are in contact with one another to form a network with the resin material.

12. The number of contact points, which is the total number of contact points between the AlN whiskers per unit volume, is 0.015 / μm ３ 1.0 / μm or more ３ The resin molded article according to claim 7 or 8, wherein:

13. 9. The resin molded article according to claim 7, wherein the content of the AlN whiskers is 3.0% by mass or more and 20.0% by mass or less.

14. 9. The resin molded article according to claim 7, wherein the content of the AlN whiskers is 50.0% by mass or more and 65.0% by mass or less.

15. A fiber-shaped AlN single crystal body, and an AlN whisker having an oxygen-containing layer covering the surface of the AlN single crystal body and an aspect ratio of 5.0 to 50,000; A resin material; A method for producing a resin molded product comprising at least forming a sheet-like structure in which a plurality of the AlN whiskers are in contact with each other to form a network; impregnating the sheet-like product with the resin material; A method for producing a resin molded product comprising the steps of:

16. A fiber-shaped AlN single crystal body, and an AlN whisker having an oxygen-containing layer covering the surface of the AlN single crystal body and an aspect ratio of 5.0 to 50,000; A spherical resin material; A method for producing a resin molded product comprising at least forming a coated structure in which a surface of each of a plurality of the resin materials is coated with a plurality of the AlN whiskers; pressing the formed coating formation; A method for producing a resin molded product comprising the steps of:

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